At present, orally administered drugs are marketed as solid preparations such as uncoated tablets, coated tablets, capsules, powders, and granules; liquid preparations such as liquids and emulsions; and the like. Orally disintegrating tablets and rapidly dissolving oral films are already on the market as preparations that disintegrate in the mouth and are absorbed by the gastrointestinal tract.
Orally administrated film-, tape-, or sheet-form preparations that are to be disintegrated or dissolved by saliva without being chewed are already available as ten or more over-the-counter drugs (OTC drugs) overseas. In Japan, those preparations are available as one ethical pharmaceutical, as well as over-the-counter drugs.
The following Patent Documents teach technologies relating to such film-form preparations. Patent Document 1 discloses a base for a preparation which is obtained by dissolving, in a solvent, hydroxypropyl cellulose or a mixture of hydroxypropyl cellulose with polyvinylpyrrolidone, and a tannin substance, and then removing the solvent. Patent Document 2 discloses a film-form troche which is obtained by laminating a coating layer (a) containing a water-soluble, non-hygroscopic polysaccharide and a softener, a drug layer (b) containing a drug and an edible water-soluble polymer, and a drug layer (c) containing a drug, an edible water-soluble polymer, and a tannin substance in the order of (a), (b), (c), (b), and (a). Patent Document 3 discloses a rapidly dissolving film-form preparation which contains a drug and an edible polymer substance, has a film breaking strength of 200 to 3000 g/φ 7 mm and a film tensile strength of 200 to 3000 g/15 mm, and melts within 60 seconds in the mouth. Patent Document 4 discloses an oral film preparation that contains one of a pregelatinized starch and pullulan; an enzyme-modified starch; and a plasticizer. Patent Document 5 discloses a soluble film preparation which contains an active ingredient having a water solubility of about less than 1 g/4 mL at room temperature, and has a moisture content of about less than 15 wt %. Patent Document 6 discloses a film-form preparation which contains a drug, an edible water-soluble film forming agent, and low-substituted hydroxypropyl cellulose with a molar substitution degree of 0.05 to 1.0. Also, Patent Document 7 discloses a technology of preparing a rapidly dissolving preparation, which rapidly disintegrate or dissolve in the mouth or the like, by dissolving or dispersing a drug, saccharides, and polyvinylpyrrolidone in an organic solvent, and then removing the organic solvent.
However, the film-form bases and preparations having been disclosed up to now are produced by dispersing or dissolving a drug in a water-soluble polymer and, sugars or sugar alcohols are used for some of those bases and preparations (Patent Document 3 and Patent Document 4). In production of such bases or preparations, sugars or sugar alcohols to be used are in the dissolved in a solvent or recrystallized. For this reason, those conventional oral film-form bases or preparations give a sticky sensation attributed to the water-soluble polymer when applied in the mouth or when handled with the fingers. Patent Document 7, which relates to a rapidly dissolving preparation, teaches neither a technology of dispersing fine particles of saccharides nor production of a film-form preparation.    Patent Document 1: JP 7-187993 A    Patent Document 2: JP 2001-288074 A    Patent Document 3: JP 2004-43450 A    Patent Document 4: JP 2005-21124 A    Patent Document 5: JP 2007-528876 T    Patent Document 6: JP 2008-169138 A    Patent Document 7: JP 11-116465 A